Clinical applicability of monitoring pulmonary artery blood flow acceleration time variations in monitoring fetal pulmonary artery pressure.

Background: In recent years, pulmonary artery blood flow acceleration time (AT) has been believed to be applicable in the examination of fetal lung development.

Objectives: This study aims to evaluate the clinical significance of pulmonary artery blood flow AT as a parameter in monitoring of fetal pulmonary artery pressure.

Material And Methods: A total of 31 fetuses in midor late-term pregnancy with tricuspid regurgitation were set as the study group (congenital heart disease with a tricuspid regurgitation pressure difference of more than 20 mm Hg was excluded). A total of 68 normal fetuses in midor late-term pregnancy were selected as the control group (strictly screened for tricuspid regurgitation, congenital heart disease and other congenital diseases before inclusion). The average ATs of both groups were calculated. Correlations of pulmonary artery systolic pressure (PASP) and AT, as well as the ratio of AT to right ventricular ejection time (ET) (AT/ET ratio) of both groups were investigated by 1-way analysis of variance (ANOVA).

Results: The average AT of the study group was significantly lower than that of the control group (p < 0.0001). In the study group, AT negatively correlated with PASP (r = -0.52; p < 0.01), AT/ET ratio negatively correlated with PASP (r = -0.52; p < 0.01) and both showed statistical significance.

Conclusions: The results indicated that fetuses in the study group showed lower ATs and AT/ET ratios than the control group. Acceleration times and AT/ET ratios decreased as PASP increased. Thus, AT and AT/ET ratio can be used clinically as new parameters for the qualitative and - to some extent - quantitative evaluation of fetal pulmonary artery pressure.